I like the short Sigma zooms, the 28 to70 2.8 is really good lens, I bought one back in the early '90's and almost never took it off one of my N90's . They just brought out a new one that is even better. Unfortunately my new 24 -70 2.8 is not as good though even more robust. My experience with the 70-210 2.8 Sigma was not as good; the lens was sharp enough but very flat plus it had a lot of mechanical problems so it spent a lot of time at Sigma being repaired. I now use only an old 80-200 2.8 Nikkor that is very sharp and rugged. If I had to do it over I would buy a used Nikkor. Incidently, my new 12 to 24 Tokina is a great bargain, I like it better than the Nikon 12-24 at half the price or less.

It is common for the image shot through a teleconverter to be softer or not to the same standard as the original lense. After all you are putting another set of lense surfaces in the light path. These converters are not optimized for the lense that you are using. So they do not optimize the light transmission to the "film" surface exactly in the correct "registration" causing a subtle blur, smear, or softness to occur.

I have read great things about the 70-200 f/2.8D G-AFS ED-IF VR lens, but thought I would take a gander at the Sigma EX lens which has everything but the VR, and at half the price. That is the Sigma 70-200mm f/2.8 EX DG APO HSM.

Man these lens manufact. really put in the alphabet soup when naming their lenses.

But anyway has anyone had experience that you would like to share using the Sigma lens above with Nikon equipment? Was it good, bad? indifferent? Is giving up VR that big a deal? I do plan to hand hold the camera for some shots when I have to. And a fast shutter speed will help with some of this, but I also plan to get a 2x doubler for whichever one I go with. So any comments using the Sigma lens with a doubler would be much appreciated as well.

By the way I am staying pretty much in this range because of the f2.8 at the bright end. I know that 2x will lose me 2 f stops but the 200-400 Nikon is only one stop brighter at f4 and the 130-300 Sigma is also one stop brighter, but economies of scale prevent me from laying out the cash for one of these (I am sure) excellent lenses. Seeing as how I do not plan to use the upper end all that often and am willing to take slightly lower resolution at those times. With the D70 and a 2x doubler I will be working with the equivalent of a 600mm zoom at he top end.

Another reason I am staying in the 70-200 range is that the 70mm bottom end is where my kit lens stops. I have the 18-70 that came with the D70. So with 2 lens and a doubler I am covered from 27mm (effective) all the way out to 600mm (effective) with just two lenses. Eventually I will have to see about getting a 10 or 12mm for the wide angle stuff, but so far the 18 mm has been enough for that.

Or compare and contrast these 2 lenses or advice to chuck both of them and go with something else.

Another question: what do you use for teleconverters? I was just in my camera shop yesterday and was trying out the 80-200 nikkor mentioned above and then hooked up a Kenko 2x teleconverter (on a D70) and noticed a marked difference in sharpness at the top end of the zoom. And this was on the tiny display on the back of the camera.

Is that normal for the teleconverters or did I just draw a marginal specimen?